Content item activity feed for presenting events associated with content items

ABSTRACT

A content management system provides event data relating to other users&#39; activity or interactions with a content item for display in an activity feed provided in conjunction with a user interface of a native application displaying the content item. Though provided in conjunction with the native application, the event data is maintained separate from the content data of the content item and displayed in the activity feed by an application separate from the native application of the content item. The activity feed permits users to exchange chat messages and retrieve information for multiple versions of the content item.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/865,972, filed Sep. 25, 2015, now U.S. Pat. No. 9,898,172, which isincorporated by reference in its entirety.

BACKGROUND

This disclosure relates generally to maintaining and providinginformation for a content item for display, and particularly tomaintaining information corresponding to content item events andproviding this information to users for display.

Content management systems permit devices to synchronize content itemswith a content management system and other devices. A device stores alocal copy of content items. When content items are added, deleted, oredited on a device, these modifications are sent to the contentmanagement system for storage and synchronization with other devices. Tointeract with a content item, users typically execute a nativeapplication on the device to view and modify the content item.Modifications to a content item may be synchronized with the contentmanagement system separately from the execution of the nativeapplication.

Accordingly, multiple users may use respective devices to separatelyview and edit a particular content item. When multiple userscollaboratively edit, draft, or otherwise work with the same contentitem, however, it becomes difficult for the users identify changes madeby other users, to determine if they have opened the latest version ofthe content item, to know if other users have made changes to thecontent item since they last opened the content item, and so forth. Suchan environment where multiple users are separately viewing and editing acontent item can lead to confusion and other inefficiencies.

SUMMARY

A content management system maintains a content event log storingcontent item event data and other metadata relating to revisions, edits,user chat messages or comments, and other interactions made to a contentitem, and provides this event information for display in an activityfeed to the client devices of the various users. The event informationin the activity feed enables users who have access to the document toidentify edits to the document, as well as different versions of thedocument, comment on the document itself, and exchange messages withother users, without necessarily modifying the actual content data ofthe document to store the comments and messages associated with thedocument.

A computing device, via a client application of the content managementsystem, stores a local copy of a shared content item that is alsostored, maintained, and synchronized between devices by the contentmanagement system. The device also includes a native contentapplication, such as a word processor, media viewer, media editor, andso forth that can be used to access the content item. The nativeapplication displays content data of the content item in a userinterface element, such as a window. The client application isprogrammatically configured to interact with the content managementsystem and access the content event log to monitor activity orinteractions with the content item on the device and communicateinformation about these events to the content management system, whichthen provides this data to other devices sharing the content item. Theclient application aggregates and provides the event data including datadescribing the event, such as the user generating the event, the type ofevent, when the event occurred, what version of the content item theevent corresponds to, and so forth, to facilitate collaboration betweenusers, for example.

The event data stored in the content event log can, for example, includeinteractions with the client application or the native applicationconcerning content item events, such as opening a content item, editing,revising, or making changes to a content item, saving a content item,renaming a content item, saving the content item as a new version or newdocument, moving a content item, deleting a content item, submitting amessage, and so forth. In one embodiment, the event data is received bythe client application associated with the content management system,which is separate from and independent of the native applicationinteracting with the content item. That is, in this embodiment theevents are received or gathered by another application or process thatis not, nor is it integrated into, the native application for thecontent item.

Additional types of event data can include notes, user views, messages,notification requests, and comments related to the content item that maybe received by the client application and which are also separate fromthe native application that is providing the content item. Messages mayinclude chat messages to other devices or comments referring to thecontent item. Event data can also include metadata modifications, suchas versioning notes, or requests for further information stored at thecontent management system about the content item, such as a request toview versioning information or prior content item versions. The eventdata is, for example, exchanged and displayed by the devices to provideusers with information regarding other user's interactions with ormodifications to the content item. Thus, the event data is generated forat least two types of events: exogenous events that are generated by thecontent application (for operations that take place by the contentapplication) and endogenous (generated by the client application of thecontent management system, such as messages, comments, etc.). Exogenousevents are received, and then metadata describing such exogenous eventsis generated to represent them in the event log. For endogenous events,the metadata is likewise used to represent the event.

The content management system stores and maintains the content data forthe content item and also separately stores and maintains content datafor various versions, and other updates or changes to the content item,apart from the content data of the content item itself. The updates andchanges to the content data are received by the content managementsystem via the client application and the associated event data isstored in the event log; the event log may be stored as a disk file, ina database, or in some other format. In one embodiment, each clientdevices register with the content management system and associated withmetadata to receive event data for a shared content item, may beconfigured to specify a particular activity to trigger an eventnotification. When the specified activity occurs, the event data is sentto devices associated with the content item to receive the eventnotification in an activity feed window for the content item that isseparate from the native application for the content item.

Accordingly, the client devices display the event notification relatingto other users' activity or interactions with a content item in theactivity feed that is provided in conjunction with a user interface ofthe native application concurrently displaying the content item itself.For example, the content item may be displayed in a main window, and theactivity feed window may be concurrently displayed in a side windowadjacent the main window. This permits users to view, in essentiallyreal or near real-time, the activity or progress of other users withrespect to a content item. In addition, by presenting user interfaces tocommunicate with the content management system alongside the nativecontent application, the activity feed window permits users to exchangechat messages and retrieve data about a content item while the contentitem is being displayed.

Further, because the client application is independent of nativeapplication, it can be used to provide activity feed information fornative content applications which themselves do not provide anyprogrammatic support for tracking versions, commenting, or exchangingmessages. This enables the client applications to further extend thefunctionality of such limited native applications.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an embodiment of an environment for content itemsynchronization including the display of event information to otherusers in a shared environment.

FIG. 2 shows various modules and components of a device, according toone embodiment.

FIGS. 3A and 3B show event information provided by a first user beingreflected in an activity feed for a shared content item to a seconduser.

FIGS. 4A and 4B show event information reflected in the activity feedprovided by the second user in response to the interaction of the firstuser shown in FIGS. 3A and 3B.

FIG. 5 shows the event information of FIGS. 3-4 reflected in an activityfeed for a preview of the shared content item displayed in a web browserto a third user.

FIG. 6 shows an interaction diagram for displaying activity informationfor a content item, according to one embodiment.

FIG. 7A shows an interaction diagram for generating event data on aclient device, according to one embodiment.

FIG. 7B shows an interaction diagram for receiving event data generatedby a content management system, according to one embodiment.

FIG. 8 shows components of a content management system, according to oneembodiment.

FIG. 9 shows a data schema within a content management system, accordingto one embodiment.

FIG. 10A shows an interaction diagram for generating event on a clientdevice, according to one embodiment.

FIG. 10B shows an interaction diagram for generating a new version of acontent item and event data for the new version, according to oneembodiment.

FIG. 11 shows an example process for providing event information fordisplay to users of a shared content item, according to one embodiment.

The figures depict various embodiments of the present invention forpurposes of illustration only. One skilled in the art will readilyrecognize from the following discussion that alternative embodiments ofthe structures and methods illustrated herein may be employed withoutdeparting from the principles of the invention described herein.

DETAILED DESCRIPTION

FIG. 1 shows an example system environment for content itemsynchronization providing users with an activity feed of content itemevents, such as interactions, chat messages, or comments, for a contentitem to facilitate the sharing and collaborative editing of sharedcontent items. FIG. 1 includes devices 100A, 100B, 100C (referred togenerally as device 100), content management system 110, and network120. Three devices are shown for purpose of illustration; in practice,however, any number of devices may be present in the environment.Similarly, other modules or components described and illustratedthroughout may include single or multiple instances as appropriate tothe needs of the implementer and without loss of generality.

Device 100 may be any suitable computing device for locally storing andviewing content items and synchronizing the content items with contentmanagement system 110. Examples of devices include desktop and laptopcomputers, hand-held mobile devices, tablet computers, and othercomputing devices. The operation of device 100 in various embodiments isfurther described below. In particular, each device 100 is configured bya client application 200 (described with respect to FIG. 2) that extendsthe operation of the client device 100 beyond the functionality for ageneric computer device, as will be further described, and therebyimproves the overall functionality of the device 100.

Each device 100 communicates with content management system 110 throughnetwork 120. Network 120 is any suitable network and may include localnetworks, corporate networks, global networks, and any combination ofthese. In typical configurations, devices 100 communicate via a wired orwireless communication network to a local network service provider, andcommunicate with content management system 110 through the Internet.

Content management system 110 provides content sharing andsynchronization services for users of devices 100. These services allowusers to share content with users of other devices 100. In addition tocontent sharing, content management system 110 updates shared contentresponsive to changes and enables synchronized changes to content itemsacross multiple devices 100. Users who register with content managementsystem 110 are provided with a user account and a user may synchronizecontent across multiple devices 100 associated with the user's account,and the user may share content that is synchronized with devicesassociated with other users' accounts.

Content stored by content management system 110 can include any type ofdata, such as digital data, documents, media (e.g., images, photos,videos, audio, streaming content), data files and databases, source andobject code, recordings, and any other type of data or file,collectively referred to here as “content items.” Content items storedby content management system 110 may also be used to organize othercontent items, such as folders, tables, collections, albums, playlists,or in other database structures (e.g., object oriented, key/value etc.).In practice, various devices 100 will be synchronized with differentgroups of content items, based on user associations, permissions,content sharing permissions, and so forth. The operation of contentmanagement system 110 in various embodiments is further described below.

FIG. 2 shows exemplary modules and components of device 100 inaccordance with one embodiment. Device 100 includes display 220 forproviding information to the user, and in certain client devices 100includes a touchscreen. Device 100 also includes network interface 225for communicating with content management system 110 via network 120.Device 100 also includes a user input module 260, which receives userinputs from various user input devices, such as a keyboard, a mouse, atrackpad, or other device. Other conventional components of a clientdevice 100 that are not material are not shown, for example one or morecomputer processors, local fixed memory (RAM and ROM), as well asoptionally removable memory (e.g., SD-card), power sources, andaudio-video outputs.

Software modules include operating system 245 and one or more nativeapplications 255. Native applications 255 vary based on client device,and may include various applications for creating, viewing, consuming,and modifying content stored on content management system 110, such asword processors, spreadsheets, database management systems, codeeditors, image and video editors, e-book readers, audio and videoplayers, and the like. Operating system 245 on each device provides alocal file management system and executes the various software modulessuch as content management system client application 200 and nativeapplication 255. A contact directory 240 stores information about theuser's contacts, such as name, picture, telephone numbers, company,email addresses, physical address, website URLs, and the like. Furtheroperation of native applications 255, operating system 245, and contentmanagement system client application 200 are described below.

In certain embodiments, device 100 includes additional components suchas camera 230 and location module 235. Camera 230 may be used to captureimages or video for upload to the online content management system 110.Location module 235 determines the location of device 100, using forexample a global positioning satellite signal, cellular towertriangulation, or other methods. Location module 235 may be used byclient application 200 to obtain location data and add the location datato metadata about a content item, such as an image captured by camera230.

Client device 100 accesses content management system 110 in a variety ofways. Client application 200 can be a dedicated application or modulethat provides access to the services of content management system 110,providing both user access to shared files through a user interface, aswell as programmatic access for other applications. Client device 100may also access content management system 110 through web browser 250 bysigning into a user account through a content management system webpage.As an alternative, client application 200 may integrate access tocontent management system 110 with the local file management systemprovided by operating system 245. When access to content managementsystem 110 is integrated in the local file management system, a fileorganization scheme maintained at content management system 110 isrepresented as a local file structure by operating system 245 inconjunction with client application 200. Client application 200 may takevarious forms, such as a stand-alone application, an applicationplug-in, a browser extension, and so forth. Client application 200includes user interface module 202, event management module 204, accessmodule 206, activity feed module 207, local content data store 208, andevent data store 210. The various modules and data stores are describedseparately throughout this disclosure for convenience and in variousimplementations may be combined or further divided into separatecomponents as desired. The client application 200 generally, and thevarious modules specifically, are not conventional or routine elementsof generic computing device 100.

Activity feed module 207 provides a user-interface activity feeddisplayed with the content item and includes an updated list or historyof content item events, such as when a user changes the content data ofa content item, renames the content item, creates a new version of thecontent item, views the content item, and so forth, and is one means forperforming these functions. As displayed in the activity feed, theseevents notify users of updates to the content item and are referred tocollectively herein as event notifications. Each event notification isstored by the content management system 110 in a manner thatpersistently associates it with one or more particular content items,thereby allowing the content management system 110 to selectivelyretrieve events specific to each content item, as well as to trackevents that relate to multiple content items. Thus, information helpfulto the collaborative drafting, editing, and review of shared contentitems is displayed in the activity feed with the content item. Althoughseparate from the native application of the content item, the activityfeed may integrate with the native application to appear, whendisplayed, as if the activity feed was provided by the nativeapplication. Additionally, the activity feed could be displayed separatefrom the native application of the content item. In addition todisplaying the event notifications for events pertinent to thecollaborative drafting, editing, and review of shared content items,activity feed module 207 provides a message or chat interface enablingusers to submit or provide messages in-line with the event notificationsin the activity feed. Thus, the activity feed may also provide a chatfunction for users sharing the content item. Further, maintaining theevents separate from the content items themselves, enables users who donot have the native content application necessary to edit a givencontent item installed on their client devices, to nonetheless see theevents associated with a given content item in the activity feed, aswell as contribute comments and messages. This further extends thefunctionality of the client device 100 beyond its generic capabilities.

Event management module 204 determines the event data to be provided tothe activity feed module 207 for display, and is one means forperforming this function. Event management module 204 receives varioususer interaction information corresponding to events (or other useractivity) that takes place with respect to a content item from accessmodule 206 and activity feed module 207 and additionally obtains andmanages information relating to a user's synchronized content items.Each event has data corresponding to the type of event (i.e., aretrieval/open request), the user account making the request (e.g., useror account ID), a content ID identifying the content data which theevent is associated (e.g., a unique ID, file name, pathname, or thelike) a request timestamp, prior synchronization data corresponding towhen content item 302 on device 100 was last synchronized or updated bycontent management system 110, and so forth. Events further includeevent data; for comment or message event, the data includes the text ofthe comment or message. Certain event types, such as a message event caninclude an identifier of the recipient(s) to whom the message isdirected. It should be appreciated that event management module 204could alternatively reside with content management system 110 or atleast some of the processes described herein can be performed by contentmanagement system 110.

Access module 206 provides event management module 204 with content iteminteraction information for events, such as when a user opens or closeschanges, or edits the content item and when a user renames or creates anew version of the content item, and is one means for performing thisfunction. For example, access module 206 receives data corresponding toa change to the content data of a content item, notifies eventmanagement module 204, event management module 204 sends the changes tothe content data to content management system 110, receives an eventdata update corresponding to the change from content management system110, and stores the event data update in event data store 210. In oneembodiment, access module 206 may additionally provide interactioninformation for user submitted messages received via the activity feedto event management module 204. Alternatively, the interactioninformation for message events may be provided to event managementmodule 204 by activity feed module 207.

Client application 200 may store content accessed from a content storageat content management system 110 in local content data store 208. Whilerepresented here as within client application 200, local content datastore 208 may be stored with other data for client device 100 innon-volatile storage. When local content data store 208 is stored thisway, the content is available to the user and other applications ormodules, such as native application 255, when client application 200 isnot in communication with content management system 110.

Access module 206 manages updates to local content data store 208 anduses synchronization logic to communicate with content management system110 to synchronize content modified by client device 100 with contentmaintained on content management system 110, and is one means forperforming this function. One example of such synchronization isprovided in U.S. Pat. Pub. US20150012488 filed Sep. 27, 2013 and ishereby incorporated by reference in its entirety.

Accordingly, device 100 receives content items from content managementsystem 110, stores such items to local content data store 208, wherethey may be accessed and edited with various native applications 255stored on the device 100. For example, device 100 may include a photoediting application that manipulates image content items, a wordprocessing application that permits modification of text content items,or a computer-aided design (CAD) application that permits modificationof drawing content items. Additionally, content management system 110can share a content item with other users upon user request and provideusers with read and write access.

Referring now to FIGS. 3-5 there is shown an example of thecollaborative editing that includes multiple users making changes to andcomments (i.e., messages via an activity feed) on content item 302.FIGS. 3A and 3B show content item 302 displayed on desktop 300A to afirst user (clear background) while content item 302 is also displayedon desktop 300B to a second user (striped background). In this example,content item 302 may be displayed simultaneously on desktop 300A and300B where the collaboration is in substantially real time (synchronouscollaboration), or the corresponding interactions by the different userscaptured in these figures may occur at different times (asynchronouscollaboration). In this example, content item 302 is a word processingdocument and is displayed in FIGS. 3A and 3B by native application 255such as a word processor, on both desktop 300A and 300B,

Additionally, content item 302 is displayed concurrently with activityfeed 306 on both desktops 300A and 300B, thereby providing a currentlyupdated-list or history of content item events and user submittedmessages, reflecting events that are specific to the content item 302 inessentially real time as they occur on any device that has access to thecontent item 302. In this example, activity feed 306 includes messages308 and 312, event notification 310, interaction icon 314 forselectively displaying activity feed 306, and chat or message interface318 that includes text field 320 for receiving messages from users.Starting from the top, activity feed 306 includes message 308 from afirst user providing an instruction to a second user to make a change tocontent item 302, event notification 310 shows that the second user hasperformed the instruction from the first user by creating a new versionof content item 302, and message 312 which is a question from the seconduser to the first user about changes made to content item 302.

As shown in FIGS. 3-5, the messages and event notifications displaycontent associated with the message or event notification (e.g., text ofthe message or notification) and information for the user who submittedthe message or event notification based on user account (e.g., username, user icon), when the message or event notification was submittedby the user (e.g., the timestamps in 308, 310, 312), and the version ofcontent item 302 corresponding to the message or event notification(e.g., (v2) in 308, (v3) in 310, and (v3) in 312). Additionally, asshown in FIGS. 3A and 3B, messages and event notifications correspondingto previous versions of content item 302 are simultaneously displayedwith those of the current version. For example, message 308 correspondsto version 2 of content item 302 and instructs the second user to createa new version. In response, the second user creates a new version andthis event is reflected in event notification 310 that includes anindication for the new version (v3). The messages and eventnotifications for previous versions of content item 302 can be viewed byscrolling up activity feed 306 using scroll button 316. The concurrentdisplay of notifications and messages associated with different versionsof a content item provides the user with a more complete view of theoverall history and development of the content item.

Similarly, FIGS. 4A and 4B show content item 302 displayed on desktop300A to the first user and on desktop 300B to the second user reflectingchanges made by a third user. In this example, the third user has made arevision to content item 302 (i.e., a change to the content data) byunderlining a portion of text in content item 302 and this revision issynchronized across all shared devices 100, and shown displayed ondesktops 300A and 300B. Upon receiving the changes to content item 302corresponding to the revision, content management system 110 creates anew version (v4) for content item 302 and provides event datacorresponding to the creation of the new version to shared device 100.In this example, the event data for the new version is displayed inactivity feed 306 as a revision in event notification 400. Additionally,after making the revision and causing a new version to be created, thethird user submits message 402 giving an opinion on prior changes madeby the second user and notifying the other users of the changes made tocontent item 302 (i.e., the underlining added to the text). Accordingly,since the third user submitted message 402 after the creation of the newversion (v4), message 402 is associated with the new version (v4).

FIG. 5 shows content item 302 displayed on desktop 300C to a fourth userin a web preview of content item 302 as displayed by web browser 250. Inthis example, the device of desktop 300C displaying content item 302does not include client application 200. Thus, the fourth user haslogged into their user account with content management system 110 thougha webpage to access their content items. In order to view a content itemin a web preview, content management system 110 accesses the contentitem, converts the content item from the format of its nativeapplication to a preview format, such as PDF, and renders the contentitem for display in a web browser. In this case, a user can view thecontent items as web previews or download a content item for localediting or viewing, however, changes made to a content item that isdownloaded from the web cannot be synchronized with content managementsystem 110. The web preview, thus, enables the fourth user to viewrevisions to a content item 302 made by other users and updates toactivity feed 306 in substantially real time or upon refreshing thebrowser, for example.

Activity feed 306 for a web preview, however, still includes messageinterface 318 and text field 320 to submit messages. Accordingly, inthis example, activity feed 306 is displaying event notification 502corresponding to the fourth user viewing content item 302. The fourthuser is unable to make their desired changes; however, they can submit amessage to the other users for changes they would like to have made orsee made to content item 302. Thus, in this example, the fourth usersubmits message 504 commenting on the margins of content item 302.

Additionally, FIG. 5 shows activity feed 306 displaying eventnotification 502 corresponding to the fourth user viewing content item302 at 6:19 PM. In one embodiment, event notifications for user viewsmay be displayed to other users in activity feed 306 each time a useropens content item 302 in addition to a respective user submitting acomment or making changes to content item 302. Alternatively, an eventnotification for a user view may only be provided when the user viewscontent item 302 and does not trigger any other type of event (e.g.,does not revise, create a new version, submit a message, etc.). In thisexample, event notification 502 indicates that the fourth user viewedcontent item at 6:19 PM and then submitted message 504 at 6:35 PM.

FIG. 6 shows an interaction diagram for providing activity feed 306 fordisplay in response to receiving a request from device 100 to displaycontent item 302. In this example, a native application 255 sends arequest to launch content item 302 from a file folder. The request isreceived 602 by access module 206 of client application 200. Accessmodule 206 provides event management module 204 with event data forevents, such as when a user opens, closes, revises, or edits the contentitem and when a user renames or creates a new version of the contentitem, and is one means for performing this function. Thus, in responseto receiving the request, access module sends 604 event datacorresponding to the open content item request with a content item IDfor content item 302 to event management module 204.

Accordingly, event management module 204 sends 606 an update request forthe content data and cumulative event data (i.e., data for all pastversions, views, messages, etc.) stored with content management 110using the content ID, and user account ID to determine whether thecontent data and cumulative event data stored locally in local contentdata store 208 and event data store 210, respectively, are current(i.e., no changes have been made on other devices). If there are noupdates or synchronization data available, event management module 204receives a notification indicating that there are no updates orsynchronization data available for the content data and cumulative eventdata for content item 302. If the content data or cumulative event dataare not current (i.e., there is an update or synchronization dataavailable for content item 302), event management module 204 receives608 a content data update and an event data update, thereby,synchronizing content item 302 and/or its associated event data with theversion of content item 302 stored with content management system 110.

In response to receiving the content and event data update, eventmanagement module 204 sends 610 the updated content data and updatedevent data with the content item ID for content item 302 to localcontent data store 208 and/or event data store 210. Accordingly, uponreceiving the content and event data update, local content data store208 and/or event data store 210 update 612 the content and event datastored locally. Additionally, event data for the received content itemrequest of 602 is stored 612 as a content item “open” event in eventdata store 210. Once updated locally, the content data is sent to nativeapplication 255 and the cumulative event data is sent 614 to activityfeed module 207 for display. Accordingly, content item 302 is displayedby native application 255 and the content item events corresponding tothe cumulative event data are displayed 616 by activity feed module 207as event notifications in activity feed 306.

In one embodiment, event data corresponding to changes to the contentdata of a content item is generated on content management system 110 andevent data for events that do not change the content data of the contentitem are generated on client 100. FIG. 7A shows an interaction diagramfor generating event data corresponding to a view, a message, or acomment on client 100. In this example, an event originating on clientdevice 100 is detected 702 by access module 206. In this example, accessmodule 206 identifies the event first by what content item the eventbelongs to (using the content item ID associated with the event data),then by version of the content item the event was made to, and then byevent type (e.g., a view, a message, or comment, etc.). Accordingly,access module 206 then generates and sends 704 event data for the eventto event management module 204. Event management module 204 identifies706 the event type and sends 708 the identified event data to activityfeed module 207 for display. Upon receiving the identified event data,activity feed module 207 displays 710 the event data in activity feed306. Additionally, event management module 204 sends (not shown) theevent data to content management system 110 for synchronization withother devices 100. Locally, event management module 204 sends 712 theevent data to event data store 210 where event data store 210 stores 714the event data. Event data generated on content management system 110 issimilarly received by device 100, as discussed above.

FIG. 7B shows an interaction diagram for receiving event data generatedby content management system 110. In one example, a new version of thecontent items is created each time changes to a content item are savedto content management system 110 and event data for the new version isgenerated on content management system 110 in response. Accordingly, inthis example, changes are made to a content item on device 100. Accessmodule 206 detects 716 the changes when the content item is saved.Access module 206 sends change data 718 corresponding to the changesmade to the content item to event management module 204. Eventmanagement module 204 sends change data 718 to content management system110 and provides change data 718 locally to local content data store208. Local content data store 208 stores the changes to a local copy ofthe content item on device 100.

Content management system 110 receives change data 718 and stores 720the changes to a copy of the content item stored with content managementsystem 110. In one example, content management system 110 may store thecontent item with the changes as a new version of the content item and,in response to generating the new version; content management system 110generates 724 event data 728. The event data 728 includes the variousevents associated with the content item (including any messages,comments, and so forth). The event data 728 is stored separately fromthe content data of the content item. Content management system 110sends the new version and event data 728 to each device 100 forsynchronization 726. Accordingly, event data 728 for the new version issent to device 100 and received by event management module 204. Assimilarly discussed above, event management module 204 identifies 730the event type and sends identified event data 732 to activity feedmodule 207 for display as an event notification 736 and to event datastore 210 for storage 734.

Alternatively, event management module 204 receives change data 718 fromaccess module 206 and does not subsequently provide change data 718 tolocal content data store 208 for storage. Instead, the content item isupdated on device 100 when content management system 100 sends the newversion and event data 728 to each device 100 for synchronization 726.

FIG. 8 shows components of content management system 110 of FIG. 1,according to one embodiment. In one configuration, components describedbelow with reference to content management system 110 are incorporatedinto devices 100 that share and synchronize content items withoutmanagement by content management system 110. These devices 100 maysynchronize content and share interaction information over network 120or via a direct connection as described above. In this configuration,devices 100 may incorporate functionality of synchronization module 812,conflict management module 814, Event synchronization module 816, andother modules and data stores for incorporating functionality describedbelow as provided by content management system 110. Accordingly, devices100 in this configuration operate in a peer-to-peer configuration andmay do so without content management system 110 or network 120.

When using content management system 110, to facilitate the variouscontent management services, a user can create an account with contentmanagement system 110. The account information can be maintained in useraccount database 818, and is one means for performing this function.User account database 818 can store profile information for registeredusers. In some cases, the only personal information in the user profilecan be a username and/or email address. However, content managementsystem 110 can also be configured to accept additional user information,such as password recovery information, demographics information, paymentinformation, and other details. Each user is associated with anidentifier, such as a user ID or a user name.

User account database 818 can also include account managementinformation, such as account type, e.g., free or paid; usage informationfor each user, e.g., file edit history; maximum storage spaceauthorized; storage space used; content storage locations; securitysettings; personal configuration settings; content sharing data; etc.Account management module 804 can be configured to update and/or obtainuser account details in user account database 818. Account managementmodule 804 can be configured to interact with any number of othermodules in content management system 110.

An account can be associated with multiple devices 100, and contentitems can be stored in association with an account. The stored contentcan also include folders of various types with different behaviors, orother content item grouping methods. For example, an account can includea public folder that is accessible to any user. The public folder can beassigned a web-accessible address. A link to the web-accessible addresscan be used to access the contents of the public folder. In anotherexample, an account can include a photo folder that is intended forphoto content items and that provides specific attributes and actionstailored for photos; an audio folder that provides the ability to playback audio file content items and perform other audio related actions;or other special purpose folders. An account can also include sharedfolders or group folders that are linked with and available to multipleuser accounts. The permissions for multiple users may be different for ashared folder. In one embodiment, the account is a namespace that may beassociated with several users, each of whom may be associated withpermissions to interact with the namespace.

The content can be stored in content storage 820, which is one means forperforming this function. Content storage 820 can be a storage device,multiple storage devices, or a server. Alternatively, content storage820 can be a cloud storage provider or network storage accessible viaone or more communications networks. In one configuration, contentmanagement system 110 stores the content items in the sameorganizational structure as they appear on the device. However, contentmanagement system 110 can store the content items in its own order,arrangement, or hierarchy.

Content storage 820 can also store metadata describing content items,content item types, and the relationship of content items to variousaccounts, folders, or groups. The metadata for a content item can bestored as part of the content item or can be stored separately. In oneconfiguration, each content item stored in content storage 820 can beassigned a system-wide unique identifier.

Content storage 820 can decrease the amount of storage space required byidentifying duplicate content items or duplicate segments of contentitems. In one embodiment, for example, a content item may be sharedamong different users by including identifiers of the users withinownership metadata of the content item (e.g., an ownership list), whilestoring only a single copy of the content item and using pointers orother mechanisms to link duplicates with the single copy. Similarly,content storage 820 stores content items using a version controlmechanism that tracks changes to content items, different versions ofcontent items (such as a diverging version tree), and a change history.The change history includes a set of changes that, when applied to theoriginal content item version, produces the changed content itemversion.

Content management system 110 automatically synchronizes content itemsfrom one or more devices, using synchronization module 812, which is onemeans for performing this function. The synchronization isplatform-agnostic. That is, the content items are synchronized acrossmultiple devices 100 of varying type, capabilities, operating systems,etc. For example, client application 200 synchronizes, viasynchronization module 812 at content management system 110, content inthe file system of device 100 with the content items in an associateduser account on system 110. Client application 200 synchronizes anychanges to content items in a designated folder and its sub-folders withthe synchronization module 812. Such changes include new, deleted,modified, copied, or moved files or folders. Synchronization module 812also provides any changes to content associated with device 100 toclient application 200. This synchronizes the local content at device100 with the content items at content management system 110.

Conflict management module 814 determines whether there are anydiscrepancies between versions of a content item located at differentdevices 100. For example, when a content item is modified at one deviceand a second device, differing versions of the content item may exist ateach device. Synchronization module 812 determines such versioningconflicts, for example by identifying the modification time of thecontent item modifications. Conflict management module 814 resolves theconflict between versions by any suitable means, such as by merging theversions, or by notifying the device of the later-submitted version.

A user can also view or manipulate content via a web interface generatedby user interface module 802. For example, the user can navigate in webbrowser 250 to a web address provided by content management system 110.Changes or updates to content in content storage 620 made through theweb interface, such as uploading a new version of a file, aresynchronized back to other devices 100 associated with the user'saccount. Multiple devices 100 may be associated with a single accountand files in the account are synchronized between each of the multipledevices 100.

Content management system 110 includes communications interface 800 forinterfacing with various devices 100, and with other content and/orservice providers via an Application Programming Interface (API), whichis one means for performing this function. Certain software applicationsaccess content storage 820 via an API on behalf of a user. For example,a software package, such as an app on a smartphone or tablet computingdevice, can programmatically make calls directly to content managementsystem 110, when a user provides credentials, to read, write, create,delete, share, or otherwise manipulate content. Similarly, the API canallow users to access all or part of content storage 820 through a website.

Content management system 110 can also include authenticator module 806,which verifies user credentials, security tokens, API calls, specificdevices, etc., to determine whether access to requested content items isauthorized, and is one means for performing this function. Authenticatormodule 806 can generate one-time use authentication tokens for a useraccount. Authenticator module 806 assigns an expiration period or dateto each authentication token. In addition to sending the authenticationtokens to requesting devices, authenticator module 806 can storegenerated authentication tokens in authentication token database 822.Upon receiving a request to validate an authentication token,authenticator module 806 checks authentication token database 822 for amatching authentication token assigned to the user. Once theauthenticator module 806 identifies a matching authentication token,authenticator module 806 determines if the matching authentication tokenis still valid. For example, authenticator module 806 verifies that theauthentication token has not expired or was not marked as used orinvalid. After validating an authentication token, authenticator module806 may invalidate the matching authentication token, such as asingle-use token. For example, authenticator module 806 can mark thematching authentication token as used or invalid, or delete the matchingauthentication token from authentication token database 822.

Content management system 110 includes a sharing module 810 for sharingcontent publicly or privately. Sharing content publicly can includemaking the content item accessible from any computing device in networkcommunication with content management system 110. Sharing contentprivately can include linking a content item in content storage 820 withtwo or more user accounts so that each user account has access to thecontent item. The content can also be shared across varying types ofuser accounts.

In some embodiments, content management system 110 includes a contentmanagement module 808 for maintaining a content directory thatidentifies the location of each content item in content storage 820, andallows client applications to request access to content items in thestorage 820, and which is one means for performing this function. Acontent entry in the content directory can also include a contentpointer that identifies the location of the content item in contentstorage 820. For example, the content entry can include a contentpointer designating the storage address of the content item in memory.In some embodiments, the content entry includes multiple contentpointers that point to multiple locations, each of which contains aportion of the content item.

In addition to a content path and content pointer, a content entry insome configurations also includes a user account identifier thatidentifies the user account that has access to the content item. In someembodiments, multiple user account identifiers can be associated with asingle content entry indicating that the content item has shared accessby the multiple user accounts.

To share a content item privately, sharing module 810 adds a useraccount identifier to the content entry associated with the contentitem, thus granting the added user account access to the content item.Sharing module 810 can also be configured to remove user accountidentifiers from a content entry to restrict a user account's access tothe content item.

To share content publicly, sharing module 810 generates a custom networkaddress, such as a URL, which allows any web browser to access thecontent in content management system 110 without any authentication. Thesharing module 810 includes content identification data in the generatedURL, which can later be used by content management system 110 toproperly identify and return the requested content item. For example,sharing module 810 can be configured to include the user accountidentifier and the content path in the generated URL. The contentidentification data included in the URL can be transmitted to contentmanagement system 110 by a device to access the content item. Inaddition to generating the URL, sharing module 810 can also beconfigured to record that a URL to the content item has been created. Insome embodiments, the content entry associated with a content item caninclude a URL flag indicating whether a URL to the content item has beencreated.

Event module 816 manages the event data for content management system toenable synchronization module 812 to provide the event data for displayas messages and as event notifications across devices 100. For example,event module 816 generates event data in response to the creation of anew version and provides the event data to synchronization module 812.Additionally, event module 816 receives the event data corresponding touser views, messages, comments, and so forth from event managementmodule 204 of client application 200 on devices 100. Event module 816subsequently stores the event data as part of an event record or contentevent log in content item event data store 824 of content managementsystem 110. Accordingly, the version data, user message data, view data,and so forth are eventually stored in content item event data store 824.

FIG. 9 shows the data schema within content item event data store 824for content event log 900. Content event log contains a plurality ofevent entries. In one embodiment, each event entry of content event log900 includes data for an event ID 902, a content item ID 904(“<contentID>”), a version ID 906, a timestamp 908, a user ID 910, andevent text 912. In this example, event ID 902 is an identifier that mayuniquely identify an event, connect the event to a content item, anddescribe the event type. In this example, event ID 902 include a letterand a number where the letter corresponds to the event type (i.e., newversion, comment, message, view, etc.) and the number corresponds to acount for a particular version of a content item of that event type. Inanother example, the event may include an event type ID that is separatefrom event ID 902.

Content item ID 904 is unique identifier that associates an event with aparticular content item. This enables content management system 110 tosearch content event log 900 and locate all events associated with aparticular content item. Version ID 906 represents the version ofcontent item 904 that was current at the time a particular event wastriggered. Timestamp 908 is an identifier corresponding to when theevent occurred and user ID 910 corresponds to a user account associatedwith the generation of event. Additionally, content event log 900includes event text 912 for text of a comment or message event. Contentitem event log is shown for illustrative purposes and it will beappreciated that other data and/or different representations of the datashown in content event log 900 can be provided in practice within thescope of various embodiments discussed herein.

Accordingly, FIG. 10A shows an interaction diagram for generating eventdata corresponding to a view, a message, or a comment on device 100 andsending the event data to content management system 110. As similarlydescribed above with respect to FIG. 7A, access module 206 of device 100detects 1002 an event, sends 1004 the event data for the event to eventmanagement module 204. Event management module 204 identifies 1006 theevent and causes 1008 the event data to be sent through a network toevent module 816 of content management system 110.

Event module 816 of content management system 110 receives the eventdata for the event that occurred on device 100 and synchronizes 1008other devices associated with sharing content item 302 (e.g., bymetadata of content item 302 indicating other user accounts and devicesassociated with those user accounts). Either simultaneously, before, orafter synchronizing the other devices with the event data, eventsynchronization module 816 sends 1010 the event data to content itemevent data store 824 of content management system 110 and content itemevent data store 824 stores 1012 the event data.

FIG. 10B shows an interaction diagram for generating a new version of acontent item and event data for the new version in response to receivingchanges to the content item. In this example, changes are made to acontent item on device 100. Access module 206 detects 1016 the changeswhen the content item is saved. Access module 206 sends change data 1018corresponding to the changes made to the content item to eventmanagement module 204. Event management module 204 sends change data1018 to event module 816 of content management system 110. In responseto receiving change data 1018, event module 816 generates 1020 a newversion of the content item, sends version data 1022 for the new versionto content storage 820 for storing the new version on content management110, and provides version data 1022 to synchronization module 812.Accordingly, synchronization module 812 subsequently sends version data1022 to each client device 100 where it is initially received by eventmanagement module 204, which will coordinate its eventual storage inlocal content data store 208.

Additionally, event module 816 generates event data 1026 correspondingto the generation 1020 of the new version of the content item.Accordingly, event module 816 sends event data 1028 for the new versionevent to content item event data store 824 for storage 1030 with contentmanagement system 110, and sends event data 1028 to synchronizationmodule 812. Synchronization module 812 subsequently sends event data1028 to each client device 100 where event data 1028 is received byevent management module 204 and eventually sent to event data store 210for storage on device 100 and to activity feed module 207 to bedisplayed as an event notification in an activity feed.

FIG. 11 shows an example process for providing event information fordisplay to users of a shared content item. Content management system 110stores 1100 content data for content item 302 in content storage 820that can be retrieved by users authorized to access content item 302.For example, a first user creates content item 302 via nativeapplication 255 on device 100 and saves content item 302 to theiraccount with content management system 110. In this example, the firstuser shares content item 302 with multiple other users. In order toshare content item 302, content management system 110 may send a sharelink created by the first user that invites the other users to view andedit content item 302. In order to grant other users access to contentitem 302, content management system 110 associates metadata with contentitem 302 indicating that the invited users can now save content item 302with their user account and have content item 302 synchronized acrossall users via synchronization module 812 and event synchronizationmodule 816. Accordingly, content management system 110 provides 1002shared content item 302 for display to each user.

In order to facilitate the various features herein, content managementsystem 110 maintains 1104 content data of content item 302 for multipleversions. Additionally, content management system 110 may also maintain1106 version event data corresponding to each version of content item302 separate in content item event data store 824 from the content datastored in content storage 820. In this example, the version event datamay correspond to information associated with the creation of aparticular version, such as the user ID of the user who created arespective version, when the version was created, on what device was arespective version created, and so forth.

Further, content management system 110 maintains 1108 user message datain content item event data store 824 corresponding to the one or moremessages associated with content item 302 for each version. As above,the user message data may be maintained separate in content item eventdata store 824 from the content data of content item 302 stored incontent storage 820 and information associated with the creation of aparticular message, such as the user ID of the user submitting arespective message, when the message was submitted, on what device arespective message was submitted, and so forth. In one example, themessages are associated with a version of content item 302 that wasdisplayed when a respective message was submitted. Thus, the messagerefers to a version of content item 302 that existed at the time themessage was created.

Finally, content management system 110 provides 1110 activity feed 306for display with content item 302 to the users. Activity feed 306,though provided for display with content item 302, is separate from thecontent data of content item 302 and native application 255 associatedwith content item 302. Activity feed 306 displays the comments and eventnotifications associated with the maintained version data, and usercomment data and will display the comments and event notifications forfuture comments, changes or revisions, and new versions. In one example,content item 302 is displayed by native application 255 and activityfeed 306 is provided by content management system 110 in a layerseparate from native application 255.

In another example, content management system 110 maintains view data incontent item event data store 824 corresponding to when users open andview content item 302 and provides information corresponding to the viewdata for display as event notifications. As with the revision data,version data, and user message data, the view data is maintainedseparate from the content data of content item 302.

Content management system 110 may be implemented using a singlecomputer, or a network of computers, including cloud-based computerimplementations. For the purposes of this disclosure, a computer isdevice having one or more processors, memory, storage devices, andnetworking resources. The computers are preferably server classcomputers including one or more high-performance CPUs and 1 G or more ofmain memory, as well as 500 Gb to 2 Tb of computer readable, persistentstorage, and running an operating system such as LINUX or variantsthereof. The operations of content management system 110 as describedherein can be controlled through either hardware or through computerprograms installed in computer storage and executed by the processors ofsuch server to perform the functions described herein. These systemsinclude other hardware elements necessary for the operations describedhere, including network interfaces and protocols, input devices for dataentry, and output devices for display, printing, or other presentationsof data, but which are not described herein. Similarly, conventionalelements, such as firewalls, load balancers, failover servers, networkmanagement tools and so forth are not shown so as not to obscure thefeatures of the system. Finally, the functions and operations of contentmanagement system 110 are sufficiently complex as to requireimplementation on a computer system, and cannot be performed in thehuman mind simply by mental steps.

The foregoing description of the embodiments of the invention has beenpresented for the purpose of illustration; it is not intended to beexhaustive or to limit the invention to the precise forms disclosed.Persons skilled in the relevant art can appreciate that manymodifications and variations are possible in light of the abovedisclosure.

Some portions of this description describe the embodiments of theinvention in terms of algorithms and symbolic representations ofoperations on information. These algorithmic descriptions andrepresentations are commonly used by those skilled in the dataprocessing arts to convey the substance of their work effectively toothers skilled in the art. These operations, while describedfunctionally, computationally, or logically, are understood to beimplemented by computer programs or equivalent electrical circuits,microcode, or the like. Furthermore, it has also proven convenient attimes, to refer to these arrangements of operations as modules, withoutloss of generality. The described operations and their associatedmodules may be embodied in software, firmware, hardware, or anycombinations thereof.

Any of the steps, operations, or processes described herein may beperformed or implemented by a combination of hardware and softwaremodules, alone or in combination with other devices. In one embodiment,a software module is implemented with a computer program productcomprising a non-transitory computer-readable medium containing computerprogram code, which can be executed by a computer processor forperforming any or all of the steps, operations, or processes described.

Finally, the language used in the specification has been principallyselected for readability and instructional purposes, and it may not havebeen selected to delineate or circumscribe the inventive subject matter.It is therefore intended that the scope of the invention be limited notby this detailed description, but rather by any claims that issue on anapplication based hereon. Accordingly, the disclosure of the embodimentsof the invention is intended to be illustrative, but not limiting, ofthe scope of the invention, which is set forth in the following claims.

What is claimed is:
 1. A method executed by a content management system,the method comprising: providing, by the content management system, acontent item for display to a first user account on a first computingdevice in a native application of the content item and to a second useraccount on a second computing device, the content item comprisingcontent data; maintaining, by the content management system, the contentdata for each of a plurality of versions of the content item and versiondata associated with creation of each of the plurality of versions;receiving, by the content management system, an indication that thefirst user account on the first computing device requested to access thecontent item, the indication comprising an update request for contentdata updates and a version data update, the update request received bythe content management system from a first client application of thefirst computing device based on update information for the updatedcontent item, the update information received by the first clientapplication of the first computing device from the native application,the first client application and the native application operatingseparately; and providing, by the content management system, an activityfeed separate from the content data and the native application of thecontent item to the first client application for display to the firstclient application in coordination with providing an updated contentitem for display to the native application on the first computingdevice, the activity feed also provided for display to a second clientapplication of the second computing device, the activity feed comprisingone or more notifications notifying the first user account and thesecond user account of the version data update, the content data updatesprovided to the first client application for display at the nativeapplication in coordination with providing for display the activity feedto the first client application.
 2. The method of claim 1, wherein thefirst computing device includes the first client application associatedwith the content management system enabling the first user account toview and edit the content item in a native application associated withthe content item, the second computing device not including the nativeapplication, and wherein providing the content item for display on thesecond computing device includes: receiving, from the second computingdevice, a request for a preview of the content item, the previewdisplaying the content item in a file format other than a native fileformat associated with the native application; providing the contentitem in the native file format for display in a preview of the nativefile; and providing the preview to the second computing device fordisplay.
 3. The method of claim 1, wherein the content item is displayedby a native application associated with the content item and theactivity feed is provided by the content management system in a layerseparate from the native application.
 4. The method of claim 1, furthercomprising: receiving, from the first user account, a change to thecontent data of the content item, the change corresponding to the firstuser account saving changes made to the content data of the contentitem; storing the change to the content data of the content item as anew version; and providing a new notification corresponding to the newversion in the activity feed for display on the first computing deviceand the second computing device.
 5. The method of claim 1, furthercomprising: associating the content item with access data indicatingthat the first user account and the second user account have access tothe content item; maintaining view data corresponding to the first useraccount or the second user account opening and viewing the content item;and providing information corresponding to the view data for inclusionwith the one or more messages to be displayed as the one or morenotifications in the activity feed.
 6. The method of claim 1, furthercomprising: maintaining, for each version of the content item, usermessage data corresponding to one or more messages associated with thecontent item submitted by the first user account or the second useraccount, wherein a message of the one or more messages is associatedwith a version of a plurality of versions of the content item that wasdisplayed when the message was submitted.
 7. The method of claim 1,wherein each version of a plurality of versions of the content itemincludes a timestamp and a user identifier, and wherein thenotifications displayed in the activity feed include the timestamp andthe user identifier of a user account associated with creating theversion.
 8. A method executed by a content management system, the methodcomprising: providing, by a content management system, a content itemfor display to a first user account on a first computing device in anative application of the content item and to a second user account on asecond computing device, the content item comprising content data;providing, by the content management system, an activity feed fordisplay with the content item separate from the content data and thenative application of the content item, the activity feed being providedfor display to a first client application of the first computing devicein coordination with providing an updated content item for display tothe native application on the first computing device, the activity feedalso provided for display to a second client application of the secondcomputing device; maintaining, by the content management system,separate from the content data and the native application of the contentitem, message data for one or more messages associated with the contentitem submitted by at least one of the first user account on the firstcomputing device and the second user account on the second computingdevice; receiving, by the content management system, an indication thatthe first user account on the first computing device requested to accessthe content item, the indication comprising an update request forcontent data updates, the update request received by the contentmanagement system from the first client application of the firstcomputing device based on update information for the updated contentitem, the update information received by the first client application ofthe first computing device from the native application, the first clientapplication and the native application operating separately; andresponsive to receiving a message submitted to the activity feed by thesecond user account, providing the message for display to the firstclient application, the content data updates provided to the firstclient application for display at the native application in coordinationwith providing for display the activity feed to the first clientapplication.
 9. The method of claim 8, further comprising: maintainingcontent data for each of a plurality of versions of the content item andversion data associated with creation of each version of the contentitem; receiving, from the first user account, a change to the contentdata of the content item, the change corresponding to the first useraccount saving changes made to the content data of the content item;storing the change to the content data of the content item as a newversion; and providing a notification for the new version for display inthe activity feed on the first computing device and the second computingdevice.
 10. The method of claim 9, wherein each message of the one ormore messages is associated with a version of the plurality of versionsof the content item that was displayed when the message was submitted,wherein messages of the one or more messages associated with previousversions of the content item are concurrently displayable with a currentversion of the content item in the activity feed.
 11. The method ofclaim 9, wherein each version of the plurality of versions includes atimestamp and a user identifier, and wherein notifications displayed inthe activity feed include the timestamp and the user identifier of auser account associated with creating the version.
 12. The method ofclaim 8, further comprising: associating, by the content managementsystem, the content item with access data indicating that the first useraccount and the second user account have access to the content item;maintaining view data corresponding to the first user account or thesecond user account opening and viewing the content item; and providinginformation corresponding to the view data for inclusion with the one ormore messages to be displayed as the one or more notifications in theactivity feed.
 13. The method of claim 8, wherein the content item isdisplayed by a native application associated with the content item andthe activity feed is provided by the content management system in alayer separate from the native application.
 14. A system comprising: atleast one processor configured to execute instructions; anon-transitory, non-volatile storage medium containing instructions thatwhen executed by the at least one processor cause the system to: providea content item for display on a first computing device in a nativeapplication of the content item and a second computing device, thecontent item comprising content data; maintain the content data for eachof a plurality of versions of the content item and version data for eachof the plurality of versions indicating whether a first user account ora second user account created a respective version; provide an activityfeed separate from the content data and the native application of thecontent item to a first client application of the first computing devicefor display by the first client application, the activity feed beingprovided for display at the first computing device in coordination withthe content item displayed by the native application on the firstcomputing device, the activity feed also provided for display to asecond client application of the second computing device, the activityfeed displaying at least one of changes or updates to the version dataor the content data of the content item; receive, from the first useraccount, a change to the content data of the content item; store thechange to the content data of the content item as a new version; andprovide new information corresponding to the new version for display onthe activity feed with the content item on the first computing deviceand the second computing device, the new version provided to the firstclient application for display at the native application in coordinationwith providing for display the activity feed to the first clientapplication.
 15. The system of claim 14, wherein the first computingdevice includes the first client application associated with a contentmanagement system allowing the first user account to view and edit thecontent item in the native application associated with the content item,the second computing device not including the native application. 16.The system of claim 15, wherein providing the content item for displayon the second computing device includes: receiving, from the secondcomputing device, a request for a preview of the content item, thepreview displaying the content item in a file format other than a nativefile format associated with the native application; providing thecontent item in the native file format for display in a preview of thenative file; and providing the preview to the second computing devicefor display.
 17. The system of claim 14, wherein the content item isdisplayed by a native application associated with the content item onthe first computing device and the activity feed is provided by thecontent management system in a layer separate from the nativeapplication.
 18. The system of claim 14, further comprising:maintaining, for each version of the content item, user message datacorresponding to one or more messages associated with the content itemsubmitted by the first user account or the second user account, whereina message of the one or more messages is associated with a version ofthe plurality of versions of the content item that was displayed whenthe message was submitted.
 19. The system of claim 18, furthercomprising: associating the content item with access data indicatingthat the first user account and the second user account have access tothe content item; maintaining view data corresponding to the first useraccount or the second user account opening and viewing the content item;and providing information corresponding to the view data for inclusionwith the one or more messages to be displayed as one or morenotifications in the activity feed.
 20. The system of claim 19, whereineach version of the plurality of versions includes a timestamp and auser identifier, and wherein the notifications displayed in the activityfeed include the timestamp and the user identifier of a user accountassociated with creating the version.